Adjustable back support for chair irons



G. D..SICKERT ADJUSTABLE BACK SUPPORT FOR CHAIR moss Aug. 15, 195 0 2 Sheets-Sheet 1 Filed Aug. 2, 1946 INVENTOR. Gene; .DSZc/I'er BY Q "6% %mm *W G. D. SICKERT I ADJUSTABLE BACK SUPPORT FOR 0mm mm Aug. '15, 1950 FiledAug. 2, 1946 1' Patented Aug. 15, 1950 ADJUSTABLE BACK SUPPORT FOR CHAIR. IRONS Gene D. Sickert, Port Washington, Wis., assignor to The Seng Company, a corporation of Illinois Application August 2, 1946, Serial No. 687,889

3 Claims. 1

This invention relates to chair irons of the type used in swivel chairs, and the like, and more particularlyto an improved mechanism for adjusting the angle of the back supporting member with respect to the remainder of the chair iron.

The primary object of the invention is to provide a simple and reliable mechanism wherein the angle of the back rest can readily be adjusted by turning a hand wheel.

The invention is illustrated in a preferred embodiment in the accompanying drawings in which Figure 1 is a side elevational view of a swivel chair embodying the invention; Fig. 2 is a fragmentary bottom plan view, taken as indicated at line 2-2 of Fig. 1; Fig. 3 is a fragmentary vertical sectional view, taken as indicated at line 3-3 of Fig. 1; and Fig. 4, a fragmentary sectional view, taken as indicated at line 4-4 of Fig. 2.

In the embodiment illustrated, a chair iron has a threaded spindle 5 mounted for vertical adjustment in a base member 6 having legs 1 provided with casters 8.

A head piece 9 is fixedly mounted on the spindle and is shown provided with a spider ID, to which a seat member Il may be fastened. A

supporting member I2 is pivotally mounted at 13 in the head piece 9, and it may swing downwardly opposed by a compression spring l4 having a tensioning member IS in the usual manner.

A back supporting plate 16 has rearwardly extending wings H, to be engaged adjustably by arms 18 on a back member l9 and locked in position by means of a bolt 20, provided with a hand wheel 2|. A yoke 22 has forwardly extending arms which are pivotally connected to the supporting member I2 by means of a wrist pin 23. The back supporting plate I6 is also provided with a second forwardly extending yoke which is riveted to the plate l6, as indicated at 24, and has two spaced arms 25 which are provided at their front ends with cam-like heads 26.

An adjusting bolt 21 extends upwardly between said heads 26 and makes a threaded connection with the supporting member [2, as indicated at 28. The bolt has a shoulder 29 whose diameter isextended by a pair of washers 30 which engage the top of the cam heads 26. The bolt is also provided with a washer 3| which is yieldingly held against the under side of the cam heads 26 by a compression spring 32, which bears against a cam wheel 33 provided on the lower end of the bolt.

It will be understood that by turning the hand wheel 33, the cam head 26 will be raised or lowered and cause the back supporting plate to swing about the wrist pin 23, so that the back member l9 may be moved to various angular po- 2 sitions, as indicated by the dotted lines in Fig. l. The spring 32 maintains the washers in close contact with the opposite faces of the cam heads 26 and resists rotation after the desired adjust ment has been made.

The foregoing detailed description is given for clearness of understanding only, and no unnecessary limitations should be understood therefrom, for some modifications will be obvious to those skilled in the art.

I claim:

1. In a chair iron: a spindle; a head piece on said spindle; a supporting member secured to said head piece; a back supporting plate having one forwardly extending yoke pivotally connected to the rear of said supporting member, and a second forwardly extending yoke provided at its front end with cam heads; and an adjusting bolt extending upwardly between said cam heads and making a threaded connection with the supporting member, said bolt having a shoulder engaging the top of the cam heads and spring means engaging the under side of said cam heads and yieldingly urging the heads into engagement with said shoulder.

2. A chair iron comprising: a spindle; a head piece on said spindle; a supportin member secured to said head piece; a back supporting plate hinged to said supporting member; and mechanism for adjusting the angular position of said back supporting plate with respect to the supporting member including a forwardly extending arm provided at its front end with a cam head, a bolt having at one end a hand wheel and making a threaded connection at the other end with said supporting member, said bolt having an upper shoulder to limit the upward travel of .said cam head, and means on the lower portion of said bolt for limiting the downward travel of the cam head with respect to the bolt.

3. A chair iron as specified in claim 2, in which the means for limiting the downward travel of the cam head includes a washer and compression spring impaled by the bolt.

GENE D. SICKERT.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 404,628 James June 4, 1889 1,779,933 Ferris Oct. 28, 1930 1,938,226 Sims Dec. 5, 1933 FOREIGN PATENTS Number Country Date 233,519 Great Britain May 14, 1925 

